Publications by authors named "Wenwu Sun"

18 Publications

  • Page 1 of 1

Detecting functional connectivity disruptions in a translational pediatric traumatic brain injury porcine model using resting-state and task-based fMRI.

Sci Rep 2021 Jun 11;11(1):12406. Epub 2021 Jun 11.

Department of Physics and Astronomy, Franklin College of Arts and Sciences, University of Georgia, 500 D.W. Brooks Drive Rm 119, Athens, GA, 30602, USA.

Functional magnetic resonance imaging (fMRI) has significant potential to evaluate changes in brain network activity after traumatic brain injury (TBI) and enable early prognosis of potential functional (e.g., motor, cognitive, behavior) deficits. In this study, resting-state and task-based fMRI (rs- and tb-fMRI) were utilized to examine network changes in a pediatric porcine TBI model that has increased predictive potential in the development of novel therapies. rs- and tb-fMRI were performed one day post-TBI in piglets. Activation maps were generated using group independent component analysis (ICA) and sparse dictionary learning (sDL). Activation maps were compared to pig reference functional connectivity atlases and evaluated using Pearson spatial correlation coefficients and mean ratios. Nonparametric permutation analyses were used to determine significantly different activation areas between the TBI and healthy control groups. Significantly lower Pearson values and mean ratios were observed in the visual, executive control, and sensorimotor networks for TBI piglets compared to controls. Significant differences were also observed within several specific individual anatomical structures within each network. In conclusion, both rs- and tb-fMRI demonstrate the ability to detect functional connectivity disruptions in a translational TBI piglet model, and these disruptions can be traced to specific affected anatomical structures.
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http://dx.doi.org/10.1038/s41598-021-91853-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8196021PMC
June 2021

Distinguishing Coronavirus Disease 2019 Patients From General Surgery Emergency Patients With the CIAAD Scale: Development and Validation of a Prediction Model Based on 822 Cases in China.

Front Med (Lausanne) 2021 30;8:601941. Epub 2021 Apr 30.

Department of General Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.

During the epidemic, surgeons cannot identify infectious acute abdomen patients with suspected coronavirus disease 2019 (COVID-19) immediately using the current widely applied methods, such as double nucleic acid detection. We aimed to develop and validate a prediction model, presented as a nomogram and scale, to identify infectious acute abdomen patients with suspected COVID-19 more effectively and efficiently. A total of 584 COVID-19 patients and 238 infectious acute abdomen patients were enrolled. The least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression analyses were conducted to develop the prediction model. The performance of the nomogram was evaluated through calibration curves, Receiver Operating Characteristic (ROC) curves, decision curve analysis (DCA), and clinical impact curves in the training and validation cohorts. A simplified screening scale and a management algorithm were generated based on the nomogram. Five potential COVID-19 prediction variables, fever, chest CT, WBC, CRP, and PCT, were selected, all independent predictors of multivariable logistic regression analysis, and the nomogram, named the COVID-19 Infectious Acute Abdomen Distinguishment (CIAAD) nomogram, was generated. The CIAAD nomogram showed good discrimination and calibration, and it was validated in the validation cohort. Decision curve analysis revealed that the CIAAD nomogram was clinically useful. The nomogram was further simplified as the CIAAD scale. We established an easy and effective screening model and scale for surgeons in the emergency department to use to distinguish COVID-19 patients. The algorithm based on the CIAAD scale will help surgeons more efficiently manage infectious acute abdomen patients suspected of having COVID-19.
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http://dx.doi.org/10.3389/fmed.2021.601941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119634PMC
April 2021

Association of Early-Phase In-Hospital Glycemic Fluctuation With Mortality in Adult Patients With Coronavirus Disease 2019.

Diabetes Care 2021 04 21;44(4):865-873. Epub 2021 Jan 21.

Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, and Ministry of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China

Objective: To investigate the association of in-hospital early-phase glycemic control with adverse outcomes among inpatients with coronavirus disease 2019 (COVID-19) in Wuhan, China.

Research Design And Methods: The study is a large case series, and data were obtained regarding consecutive patients hospitalized with COVID-19 in the Central Hospital of Wuhan between 2 January and 15 February 2020. All patients with definite outcomes (death or discharge) were included. Demographic, clinical, treatment, and laboratory information were extracted from electronic medical records. We collected daily fasting glucose data from standard morning fasting blood biochemistry to determine glycemic status and fluctuation (calculated as the square root of the variance of daily fasting glucose levels) during the 1st week of hospitalization.

Results: A total of 548 patients were included in the study (median age 57 years; 298 [54%] were women, and = 99 had diabetes [18%]), 215 suffered acute respiratory distress syndrome (ARDS), 489 survived, and 59 died. Patients who had higher mean levels of glucose during their 1st week of hospitalization were older and more likely to have a comorbidity and abnormal laboratory markers, prolonged hospital stays, increased expenses, and greater risks of severe pneumonia, ARDS, and death. Compared with patients with the lowest quartile of glycemic fluctuation, those who had the highest quartile of fluctuation magnitude had an increased risk of ARDS (risk ratio 1.97 [95% CI 1.01, 4.04]) and mortality (hazard ratio 2.73 [95% CI 1.06, 7.73]).

Conclusions: These results may have implications for optimizing glycemic control strategies in COVID-19 patients during the early phase of hospitalization.
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http://dx.doi.org/10.2337/dc20-0780DOI Listing
April 2021

Serum Cystatin C and Coronavirus Disease 2019: A Potential Inflammatory Biomarker in Predicting Critical Illness and Mortality for Adult Patients.

Mediators Inflamm 2020 8;2020:3764515. Epub 2020 Oct 8.

Intensive Care Unit, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

This study aimed at determining the relationship between baseline cystatin C levels and coronavirus disease 2019 (COVID-19) and investigating the potential prognostic value of serum cystatin C in adult patients with COVID-19. 481 patients with COVID-19 were consecutively included in this study from January 2, 2020, and followed up to April 15, 2020. All clinical and laboratory data of COVID-19 patients with definite outcomes were reviewed. For every measure, COVID-19 patients were grouped into quartiles according to the baseline levels of serum cystatin C. The highest cystatin C level was significantly related to more severe inflammatory conditions, worse organ dysfunction, and worse outcomes among patients with COVID-19 ( values < 0.05). In the adjusted logistic regression analyses, the highest cystatin C level and ln-transformed cystatin C levels were independently associated with the risks of developing critically ill COVID-19 and all-cause death either in overall patients or in patients without chronic kidney disease ( values < 0.05). As a potential inflammatory marker, increasing baseline levels of serum cystatin C might independently predict adverse outcomes for COVID-19 patients. Serum cystatin C could be routinely monitored during hospitalization, which showed clinical importance in prognosticating for adult patients with COVID-19.
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http://dx.doi.org/10.1155/2020/3764515DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7545455PMC
October 2020

Clinical characteristics of "re-positive" discharged COVID-19 pneumonia patients in Wuhan, China.

Sci Rep 2020 10 15;10(1):17365. Epub 2020 Oct 15.

Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

To analyze the clinical characteristics of re-positive discharged COVID-19 patients and find distinguishing markers. The demographic features, clinical symptoms, laboratory results, comorbidities, co-infections, treatments, illness severities and chest CT scan results of 267 patients were collected from 1st January to 15th February 2020. COVID-19 was diagnosed by RT-PCR. Clinical symptoms and nucleic acid test results were collected during the 14 days post-hospitalization quarantine. 30 out of 267 COVID-19 patients were detected re-positive during the post-hospitalization quarantine. Re-positive patients could not be distinguished by demographic features, clinical symptoms, laboratory results, comorbidities, co-infections, treatments, chest CT scan results or subsequent clinical symptoms. However, re-positive rate was found to be correlated to illness severity, according the Acute Physiology and Chronic Health Evaluation II (APACHE II) severity-of-disease classification system, and the confusion, urea, respiratory rate and blood pressure (CURB-65) score. Common clinical characteristics were not able to distinguish re-positive patients. However, severe and critical cases classified high according APACHE II and CURB-65 scores, were more likely to become re-positive after discharge.
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http://dx.doi.org/10.1038/s41598-020-74284-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7562721PMC
October 2020

Clinical Course and Mortality of Stroke Patients With Coronavirus Disease 2019 in Wuhan, China.

Stroke 2020 09 31;51(9):2674-2682. Epub 2020 Jul 31.

Intensive Care Unit (L.Z., W.S., Y.W., X.W., Y.L., D.L., L.Y.), the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, China.

Background And Purpose: No studies have reported the effect of the coronavirus disease 2019 (COVID-19) epidemic on patients with preexisting stroke. We aim to study the clinical course of COVID-19 patients with preexisting stroke and to investigate death-related risk factors.

Methods: We consecutively included 651 adult inpatients with COVID-19 from the Central Hospital of Wuhan between January 2 and February 15, 2020. Data on the demography, comorbidities, clinical manifestations, laboratory findings, treatments, complications, and outcomes (ie, discharged or death) of the participants were extracted from electronic medical records and compared between patients with and without preexisting stroke. The association between risk factors and mortality was estimated using a Cox proportional hazards regression model for stroke patients infected with severe acute respiratory syndrome coronavirus 2.

Results: Of the 651 patients with COVID-19, 49 with preexisting stroke tended to be elderly, male, had more underlying comorbidities and greater severity of illness, prolonged length of hospital stay, and greater hospitalization expenses than those without preexisting stroke. Cox regression analysis indicated that the patients with stroke had a higher risk of developing critical pneumonia (adjusted hazard ratio, 2.01 [95% CI, 1.27-3.16]) and subsequent mortality (adjusted hazard ratio, 1.73 [95% CI, 1.00-2.98]) than the patients without stroke. Among the 49 stroke patients, older age and higher score of Glasgow Coma Scale or Sequential Organ Failure Assessment were independent risk factors associated with in-hospital mortality.

Conclusions: Preexisting stroke patients infected with severe acute respiratory syndrome coronavirus 2 were readily predisposed to death, providing an important message to individuals and health care workers that preventive measures must be implemented to protect and reduce transmission in stroke patients in this COVID-19 crisis.
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http://dx.doi.org/10.1161/STROKEAHA.120.030642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7434009PMC
September 2020

Perinatal Docosahexaenoic Acid Supplementation Improves Cognition and Alters Brain Functional Organization in Piglets.

Nutrients 2020 Jul 15;12(7). Epub 2020 Jul 15.

Department of Foods and Nutrition, College of Family and Consumer Sciences, University of Georgia, Athens, GA 30602, USA.

Epidemiologic studies associate maternal docosahexaenoic acid (DHA)/DHA-containing seafood intake with enhanced cognitive development; although, it should be noted that interventional trials show inconsistent findings. We examined perinatal DHA supplementation on cognitive performance, brain anatomical and functional organization, and the brain monoamine neurotransmitter status of offspring using a piglet model. Sows were fed a control (CON) or a diet containing DHA (DHA) from late gestation throughout lactation. Piglets underwent an open field test (OFT), an object recognition test (ORT), and magnetic resonance imaging (MRI) to acquire anatomical, diffusion tensor imaging (DTI), and resting-state functional MRI (rs-fMRI) at weaning. Piglets from DHA-fed sows spent 95% more time sniffing the walls than CON in OFT and exhibited an elevated interest in the novel object in ORT, while CON piglets demonstrated no preference. Maternal DHA supplementation increased fiber length and tended to increase fractional anisotropy in the hippocampus of offspring than CON. DHA piglets exhibited increased functional connectivity in the cerebellar, visual, and default mode network and decreased activity in executive control and sensorimotor network compared to CON. The brain monoamine neurotransmitter levels did not differ in healthy offspring. Perinatal DHA supplementation may increase exploratory behaviors, improve recognition memory, enhance fiber tract integrity, and alter brain functional organization in offspring at weaning.
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http://dx.doi.org/10.3390/nu12072090DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7400913PMC
July 2020

Development of a clinical decision support system for severity risk prediction and triage of COVID-19 patients at hospital admission: an international multicentre study.

Eur Respir J 2020 08 20;56(2). Epub 2020 Aug 20.

The D-Lab, Dept of Precision Medicine, GROW - School for Oncology, Maastricht University Medical Center+, Maastricht, The Netherlands.

Background: The outbreak of coronavirus disease 2019 (COVID-19) has globally strained medical resources and caused significant mortality.

Objective: To develop and validate a machine-learning model based on clinical features for severity risk assessment and triage for COVID-19 patients at hospital admission.

Method: 725 patients were used to train and validate the model. This included a retrospective cohort from Wuhan, China of 299 hospitalised COVID-19 patients from 23 December 2019 to 13 February 2020, and five cohorts with 426 patients from eight centres in China, Italy and Belgium from 20 February 2020 to 21 March 2020. The main outcome was the onset of severe or critical illness during hospitalisation. Model performances were quantified using the area under the receiver operating characteristic curve (AUC) and metrics derived from the confusion matrix.

Results: In the retrospective cohort, the median age was 50 years and 137 (45.8%) were male. In the five test cohorts, the median age was 62 years and 236 (55.4%) were male. The model was prospectively validated on five cohorts yielding AUCs ranging from 0.84 to 0.93, with accuracies ranging from 74.4% to 87.5%, sensitivities ranging from 75.0% to 96.9%, and specificities ranging from 55.0% to 88.0%, most of which performed better than the pneumonia severity index. The cut-off values of the low-, medium- and high-risk probabilities were 0.21 and 0.80. The online calculators can be found at www.covid19risk.ai.

Conclusion: The machine-learning model, nomogram and online calculator might be useful to access the onset of severe and critical illness among COVID-19 patients and triage at hospital admission.
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http://dx.doi.org/10.1183/13993003.01104-2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331655PMC
August 2020

Clinical characteristics and risk factors for mortality among inpatients with COVID-19 in Wuhan, China.

Clin Transl Med 2020 Jun 4;10(2):e40. Epub 2020 Jun 4.

Intensive Care Unit, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

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http://dx.doi.org/10.1002/ctm2.40DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7300688PMC
June 2020

Association between platelet parameters and mortality in coronavirus disease 2019: Retrospective cohort study.

Platelets 2020 May 16;31(4):490-496. Epub 2020 Apr 16.

Intensive Care Unit, the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, China.

Background: Thrombocytopenia has been implicated in patients infected with severe acute respiratory syndrome coronavirus 2, while the association of platelet count and changes with subsequent mortality remains unclear.

Methods: The clinical and laboratory data of 383 patients with the definite outcome by March 1, 2020 in the Central Hospital of Wuhan were reviewed. The association between platelet parameters and mortality risk was estimated by utilizing Cox proportional hazard regression models.

Results: Among the 383 patients, 334 (87.2%) were discharged and survived, and 49 (12.8%) died. Thrombocytopenia at admission was associated with mortality of almost three times as high as that for those without thrombocytopenia ( < 0.05). Cox regression analyses revealed that platelet count was an independent risk factor associated with in-hospital mortality in a dose-dependent manner. An increment of per 50 × 10/L in platelets was associated with a 40% decrease in mortality (hazard ratio: 0.60, 95%CI: 0.43, 0.84). Dynamic changes of platelets were also closely related to death during hospitalization.

Conclusions: Baseline platelet levels and changes were associated with subsequent mortality. Monitoring platelets during hospitalization may be important in the prognosis of patients with coronavirus disease in 2019.
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http://dx.doi.org/10.1080/09537104.2020.1754383DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7171387PMC
May 2020

Repeated Aurora-A siRNA Transfection Results in Effective Apoptosis of A549 Cells Compared to Single Transfection.

Clin Lab 2016 ;62(4):697-703

Background: Suppression of Aurora kinase A (Aurora-A, AURKA) by Aurora-A siRNA has been proposed for lung tumor treatment. However, protocols using single administration have shown little benefit in some types of lung tumor. Given that transfection efficiency of Aurora-A siRNA is low due to tightly packed cells in the tumor, we hypothesized that repeated administration would result in efficient cell apoptosis.

Methods: We compared single vs. repeated transfection (thrice) in A549 cells by transfecting Aurora-A siRNA (siA) on the 1st or 1st, 2nd and 3rd day after cell seeding. A random sequence was used as the negative siRNA control (siC). Cells in the single transfection group received only transfection reagent without siRNAs on the 2nd and 3rd day.

Results: Two days after the third transfection, both single and repeated siA administration decreased mRNA expression of Aurora-A and cell viability compared to no administration and siC single administration. However, the decrease in these two indices with repeated transfection was more obvious than that following single administration: cell viability decreased to 72.8 ± 3.05% (p < 0.05) following siA single transfection and to 64.2 ± 1.99% (p < 0.05) following siA repeated transfection, compared with normal control cells, respectively. Gene expression decreased to 17 ± 16.6% (p < 0.05 vs. normal control) following siA repeated transfection and to 43.2 ± 13.0% (p < 0.05 vs. normal control) following siA single transfection.

Conclusions: Compared to single transfection, repeated Aurora-A siRNA transfection decreased Aurora-A, which, in turn, resulted in effective apoptosis of A549 cells.
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http://dx.doi.org/10.7754/clin.lab.2015.150836DOI Listing
June 2016

Comments on the article "Antioxidants as a treatment for acute pancreatitis: A meta-analysis".

Pancreatology 2016 May-Jun;16(3):324-5. Epub 2016 Jan 22.

Ruijin Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai, China. Electronic address:

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http://dx.doi.org/10.1016/j.pan.2016.01.001DOI Listing
April 2017

Cold stress increases reactive oxygen species formation via TRPA1 activation in A549 cells.

Cell Stress Chaperones 2016 Mar 3;21(2):367-72. Epub 2015 Dec 3.

Department of Respiratory Medicine, General Hospital of Shenyang Military Area Command, No. 83, Wenhua Road, Shenhe District, Shenyang, 110840, China.

Reactive oxygen species (ROS) are responsible for lung damage during inhalation of cold air. However, the mechanism of the ROS production induced by cold stress in the lung is still unclear. In this work, we measured the changes of ROS and the cytosolic Ca(2+) concentration ([Ca(2+)]c) in A549 cell. We observed that cold stress (from 20 to 5 °C) exposure of A549 cell resulted in an increase of ROS and [Ca(2+)]c, which was completely attenuated by removing Ca(2+) from medium. Further experiments showed that cold-sensing transient receptor potential subfamily member 1 (TRPA1) agonist (allyl isothiocyanate, AITC) increased the production of ROS and the level of [Ca(2+)]c in A549 cell. Moreover, HC-030031, a TRPA1 selective antagonist, significantly inhibited the enhanced ROS and [Ca(2+)]c induced by AITC or cold stimulation, respectively. Taken together, these data demonstrated that TRPA1 activation played an important role in the enhanced production of ROS induced by cold stress in A549 cell.
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http://dx.doi.org/10.1007/s12192-015-0663-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4786528PMC
March 2016

Enhanced production of nitric oxide in A549 cells through activation of TRPA1 ion channel by cold stress.

Nitric Oxide 2014 Aug 9;40:31-5. Epub 2014 May 9.

Department of Respiratory Medicine, General Hospital of Shenyang Military Area Command, Shenyang 110840, China. Electronic address:

The respiratory epithelium is exposed to the external environment, and inhalation of cold air is common during the season of winter. In addition, the lung is a major source of nitric oxide (NO). However, the effect of cold stress on the production of NO is still unclear. In the present work, We measured the change of NO in single cell with DACF-DA and the change in cytosolic Ca(2+) concentration ([Ca(2+)]c) in A549 cell. We observed that cold stress (from 20 °C to 5 °C) induced an increase of NO in A549 cell, which was completely abolished by applying an extracellular Ca(2+) free medium. Further experiments showed that cold-sensing transient receptor potential subfamily member 1 (TRPA1) channel agonist (allyl isothiocyanate, AITC) increased the production of NO and the level of [Ca(2+)]c in A549 cell. Additionally, TRPA1 inhibitor, Ruthenium red (RR) and camphor, significantly blocked the enhanced production of NO and the rise of [Ca(2+)]c induced by AITC or cold stimulation, respectively. Taken together, these data indicated that cold-induced TRPA1 activation was responsible for the enhanced production of NO in A549 cell.
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http://dx.doi.org/10.1016/j.niox.2014.04.009DOI Listing
August 2014

The effect of aerosol polyethylenimine/interferon-γ plasmid complexes on expression of inflammatory cytokines in mouse lung.

Authors:
Zhuang Ma Wenwu Sun

J Aerosol Med Pulm Drug Deliv 2014 Apr 22;27(2):117-24. Epub 2013 Jun 22.

Department of Respiratory Medicine, General Hospital of Shenyang Military Area Command , Shenyang, 110016, China .

Background: The expression of inflammatory cytokines in lung tissue plays an important role in immune function of the lung. In this study, we tested whether aerosol delivery of the gene of interferon-γ (IFNγ) could affect inflammatory cytokine expression in mouse lung.

Methods: Murine IFNγ-expressing plasmids (pcDNA-IFNγ) complexed with polyethylenimine (PEI) (PEI/pcDNA-IFNγ) were constructed, and their transfection efficiency was assessed in vivo using real-time quantitative RT-PCR and enzyme-linked immunosorbent assay. After aerosol administration of the plasmid complexes and confirmation of the IFNγ plasmid location in lung tissue, we measured mRNA levels of the inflammatory cytokines interleukin-1 (IL-1), IL-6, IL-10, tumor necrosis factor-α (TNF-α), and granulocyte-macrophage colony-stimulating factor (GM-CSF) on days 1 to 7 in mouse lung tissues using real-time RT-PCR.

Results: IFNγ mRNA expression in mouse lung was significantly increased 24 hr after a single aerosol administration of PEI/pcDNA-IFNγ and gradually decreased over the next 5 days, whereas the mRNA expressions of IL-1, IL-6, and GM-CSF were markedly decreased, but not those of IL-10 and TNF-α.

Conclusions: PEI/IFNγ gene therapy delivered by aerosol has immune-regulating potential by suppressing lung cytokine mRNA expression, and therefore may alleviate lung disease.
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http://dx.doi.org/10.1089/jamp.2012.1003DOI Listing
April 2014

Nitric oxide induces apoptosis associated with TRPV1 channel-mediated Ca(2+) entry via S-nitrosylation in osteoblasts.

Eur J Pharmacol 2013 Sep 23;715(1-3):280-5. Epub 2013 May 23.

The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, TEDA Applied Physics School and School of Physics, Nankai University, Tianjin, China.

The high-level production of nitric oxide (NO) induced by inflammatory cytokines has been shown to play a key role in the pathogenesis of inflammation-mediated osteoporosis. In the present work, we observed that 1mM of the NO donor sodium nitroprusside (SNP) induced an increase of the cytosolic calcium concentration ([Ca(2+)]c) in osteoblasts, which was completely abolished by applying an extracellular Ca(2+)-free buffer. Further experiments showed that the SNP-induced [Ca(2+)]c increase was specifically blocked by potent antagonists of the transient receptor potential vanilloid subtype 1 (TRPV1) channel: capsazepine, ruthenium red, and La(3+) in Ca(2+)-containing buffer. However, nifedipine, an L-type voltage sensitive Ca(2+)-channel blocker, failed to suppress the [Ca(2+)]c elevation caused by SNP. Additionally, 1mM SNP induced osteoblast apoptosis, which was largely inhibited by the blockers of TRPV1, capsazepine and ruthenium red. Interestingly, our data showed that the SNP-induced [Ca(2+)]c increase was significantly inhibited by N-ethylmaleimide, the blocker of S-nitrosylation modification, instead of inhibitors of the NO-cGMP-PKG pathway. Taken together, our data clearly demonstrated that the NO donor SNP resulted in apoptosis associated with TRPV1 channel-mediated Ca(2+) entry via S-nitrosylation in osteoblasts.
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http://dx.doi.org/10.1016/j.ejphar.2013.05.009DOI Listing
September 2013

Hypo-osmotic stress enhances the uptake of polyethylenimine/oligonucleotide complexes in A549 cells via Ca(2+) mobilization from intracellular stores.

Oligonucleotides 2010 Apr;20(2):111-5

Department of Respiratory Medicine, The Northern Hospital of ShenYang, Shenyang, China.

To determine the mechanism of osmolarity involved in polyethylenimine (PEI)/oligonucleotide (ON) complex transfection in cells, we measured the fluorescence intensities of fluorescein isothiocyanate-labeled ONs complexed with PEI and the changes in cytosolic Ca(2+) concentration ([Ca(2+)](c)) in A549 cells, and we found that uptake of PEI/ON complexes was improved in the cells along with a rise of [Ca(2+)](c) in A549 cells challenged by 50% hypotonic medium. Further experiments showed that the enhanced uptake efficiency and the rise in [Ca(2+)](c) in A549 cells were almost completely abolished from cells loaded with the intracellular calcium chelator 1,2-bis(2-aminophenoxy)-N,N,N,N-tetraacetic acid-acetoxymethyl ester. 2-Aminoethoxydiphenyl borate or 8-(N,N-diethylamino) octyl-3,4,5-trimethoxybenzoate, two potent antagonists of inositol 1,4,5-trisphosphate-mediated Ca(2+) release that blunt [Ca(2+)](c) elevation via Ca(2+) release from endoplasmic reticulum, inhibited the enhanced uptake of PEI/ON complexes induced by Ca(2+)-free hypo-osmotic stress. In summary, the results strongly suggest that calcium-dependent transfection is responsible for the uptake of PEI/ON complexes into A549 cells under hypotonic conditions.
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http://dx.doi.org/10.1089/oli.2009.0203DOI Listing
April 2010

Reconstruction Algorithm with Improved Efficiency and Flexibility in Multi-Slice Spiral CT.

Conf Proc IEEE Eng Med Biol Soc 2005;2005:1901-4

Nanchang Institute of Aeronautical Technology, Nanchang, China; Shenzhen Anke Hi-Tech Corporation Limited, Shenzhen, China. E-mail:

There is a requirement for the development of CT to scan rapidly large longitudinal volume with high z-axis resolution. The combination of spiral scanning with multi-slice CT is a promising approach. The algorithm of image reconstruction for multi-slice spiral CT becomes, therefore, the main challenge. All algorithms known to the authors either need to derive the complementary data or work only for certain range of pitch values. This paper presents a novel reconstruction algorithm that can omit the derivations of the complementary data and work for arbitrary pitch values. The filter interpolation based on the proposed method is also easy to be implemented. The method is, thus, versatile. The results of computer simulations show that we can choose a combination of scan and filter parameters to meet the purpose of the examination.
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http://dx.doi.org/10.1109/IEMBS.2005.1616822DOI Listing
October 2012